Can't inherit from IdentityUser and IdentityRole in ASP.NET Core 2.0

Question

I\'m trying to finish updating to .NET Core 2.0 but a couple of errors pop up:

The problem:

I have two classes, ApplicationRole and ApplicationU

Answer 1

This happen to me but I was using Asp.net Core with traditional .NET Framework. You need to add the Nuget package Microsoft.Extensions.Identity. That contains the classes IdentityUser and IdentityRole.

I think the reason you have to add this is when your project isn't using the Microsoft.AspNetCore.All package.

Answer 2

For me it got solved by installing package:

Microsoft.Extensions.Identity.Stores

Answer 3

ICollection<IdentityUserRole<int>> Roles , ICollection<IdentityUserClaim<int>> Claims and ICollection<IdentityUserLogin<int>> Logins navigation properties have been removed from Microsoft.AspNetCore.Identity.IdentityUser .

You should define them manually

public class MyUser : IdentityUser
{                
    public virtual ICollection<IdentityUserRole<int>> Roles { get; } = new List<IdentityUserRole<int>>();

    public virtual ICollection<IdentityUserClaim<int>> Claims { get; } = new List<IdentityUserClaim<int>>();

    public virtual ICollection<IdentityUserLogin<int>> Logins { get; } = new List<IdentityUserLogin<int>>();
}

To prevent duplicate foreign keys when running EF Core Migrations, add the following to your IdentityDbContext class' OnModelCreating method

protected override void OnModelCreating(ModelBuilder builder)
{
  base.OnModelCreating(builder);

builder.Entity<MyUser>()
    .HasMany(e => e.Claims)
    .WithOne()
    .HasForeignKey(e => e.UserId)
    .IsRequired()
    .OnDelete(DeleteBehavior.Cascade);

builder.Entity<MyUser>()
    .HasMany(e => e.Logins)
    .WithOne()
    .HasForeignKey(e => e.UserId)
    .IsRequired()
    .OnDelete(DeleteBehavior.Cascade);

builder.Entity<MyUser>()
    .HasMany(e => e.Roles)
    .WithOne()
    .HasForeignKey(e => e.UserId)
    .IsRequired()
    .OnDelete(DeleteBehavior.Cascade);
}

Migrating Authentication and Identity to ASP.NET Core 2.0

Answer 4

You need to install Microsoft.AspNetCore.Identity.EntityFramework package

Install-Package Microsoft.AspNetCore.Identity.EntityFramework

or

dotnet add package Microsoft.AspNetCore.Identity.EntityFramework

Answer 5

Solved.

The package that was keeping those classes Microsoft.AspNetCore.Identity.EntityFrameworkCore changed. To access those clases (IdentityUser and IdentityRole) one must add

using Microsoft.AspNetCore.Identity;

With this, the problem is gone.